Empirical bounds for the ionizing fluxes of Wolf-Rayet stars

David R. Law, Kathleen Degioia-Eastwood, Kevin L. Moore

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

Hα photometry and spectroscopic data have been obtained for 10 Wolf-Rayet nebulae, representing a wide variety of WN spectral types. We use these data to constrain the ionizing flux of the exciting Wolf-Rayet star, calculating lower bounds for the Lyman continuum flux (Q0) and for the He0- and He+ionizing fluxes (Q1 and Q2). We find that Q0 appears independent of WN spectral type, and lower bound estimates tend to cluster around 48 dex. Finally, we discuss the effects of potential shock excitation and density bounding on these nebulae and compare our results to recent models. Our results are consistent with the predictions of line-blanketed ISA-wind models and nonblanketed CMFGEN models but are consistent with only some of the line-blanketed CMFGEN models.

Original languageEnglish (US)
Pages (from-to)1239-1250
Number of pages12
JournalAstrophysical Journal
Volume565
Issue number2 I
DOIs
StatePublished - Feb 1 2002

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Wolf-Rayet stars
nebulae
wolves
photometry
shock
continuums
estimates
prediction
predictions
excitation

Keywords

  • H II regions
  • Stars: fundamental parameters
  • Stars: Wolf-Rayet

ASJC Scopus subject areas

  • Space and Planetary Science

Cite this

Empirical bounds for the ionizing fluxes of Wolf-Rayet stars. / Law, David R.; Degioia-Eastwood, Kathleen; Moore, Kevin L.

In: Astrophysical Journal, Vol. 565, No. 2 I, 01.02.2002, p. 1239-1250.

Research output: Contribution to journalArticle

Law, David R. ; Degioia-Eastwood, Kathleen ; Moore, Kevin L. / Empirical bounds for the ionizing fluxes of Wolf-Rayet stars. In: Astrophysical Journal. 2002 ; Vol. 565, No. 2 I. pp. 1239-1250.
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